1. Field of the Invention
This invention relates to an implement suspension for a vehicle-mounted implement and more particularly, in the preferred embodiment, to a mower deck.
2. Description of Related Art
In grounds care applications, vehicles are typically coupled with some sort of additional implement. For example, mower decks, front blades, and other customary implements are commonly used. Often the implements are either comparatively fixedly mounted to the frame of the vehicle, allowing little or no side-to-side articulation of the implement, or they may be provided with a suspension including a mechanism which allows for some amount of side-to-side articulation of the implement to permit the implement to follow the contour of the ground over which it passes.
One conventional implement suspension utilizes a single lift cylinder to raise and lower an implement. A pair of lift arms are swingably connected to the vehicle at one end and coupled to the implement at another. The lift arm is pinned to a lift link extending between the two lift arms. A degree of side-to side articulation of the implement is accomplished by using ball joints at each end of the lift arms where the arms are connected to the vehicle and the implement. However, there is a perceived lack of control when the implement is raised by the lift cylinder, in that the capacity for side-to-side articulation is not sufficiently diminished after the implement leaves the ground.
Another conventional implement suspension makes use of two lift cylinders which are connected to an implement at opposite ends thereof to raise and lower the implement to a desired position. As the vehicle and implement travel over the ground, the two lift cylinders may be placed in "float", whereby the cylinders are permitted to freely extend and compress within their normal limits of travel, thereby enabling the implement to articulate from side-to side in that the opposite ends of the implement may move up or down independently to follow the contour of the ground. However, the use of two lift cylinders represents a substantial increase in cost and maintenance over a suspension which uses a single lift cylinder.